Title : Putgyul (unripe citrus) improved skin wrinkling and moisture content in a doubleblind randomized clinic trial
Abstract:
Owing to the increasing demand of products that delay or prevent skin aging, various products are currently being developed. Recently, the importance of skin care from both inside and outside the body, skin condition, and influence of external environment on the skin have been emphasized, and research on functional foods that can help maintain a healthy skin is actively conducted. In this double-blind, randomized clinical trial, we evaluated skin wrinkles, water content, glossiness, elasticity, and dermal density of the skin, which change as the skin ages, to investigate the effect of putgyul (unripe citrus) in improving skin condition. The subjects who were eligible for this study were asked to take test product containing putgyul extract (PE) once daily for 12 weeks. The parameters related to skin aging were measured in the PE and control groups after 0 (no consumption), 4, 8, and 12 weeks of PE ingestion. Skin wrinkle analysis using three-dimensional images showed that wrinkles improved significantly in the PE group after 12 weeks of PE ingestion compared with that before consumption (P<0.05). In addition, skin wrinkles significantly improved in the PE group compared with the control group (P<0.05). Moisture analysis of the skin epidermis and dermis showed that the moisture content of the cheek increased significantly in the PE group after 12 weeks of PE ingestion (P<0.05). The water content in the cheek epidermis significantly improved in the PE group compared with the control group (P<0.05). However, the water content in the cheek dermis showed no significant differences between the PE and control groups. Furthermore, the PE group tended to show an increase in skin gloss at 4, 8, and 12 weeks after ingestion compared with that before ingestion. No significant differences were observed between the PE and control groups. Dermal density analysis also showed similar results to skin gloss measurement. Analysis of skin elasticity (R2 parameter) revealed that skin elasticity in PE group significantly improved at 12 weeks of PE ingestion compared with that before consumption, but there was no significant difference between the PE and control groups. All participants in the PE and control groups responded positively to the five measures of effectiveness (increase in skin moisture, increase in skin gloss, improvement of skin firmness, reduction of crow’s feet, and improvement of overall skin condition) and four measures of usability (color, ease of intake, satisfaction, and purchase intention). Nevertheless, there were no significant differences in all parameters between the PE and control groups. The analysis of skin adverse reactions revealed that erythema with itching occurred in one participant among the total 58 subjects, However, this was an isolated case and not considered a problem to skin safety as a whole, because no adverse reactions were observed in other subjects. Taken together, the findings of this study reveal that putgyul has the potential to serve as an anti-wrinkle and skin moisturizing ingredient in functional foods.
